• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2011.11a
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• pp.34-34
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• 2011

Recently, people have concerned about environmental pollution. This environmental pollution occur due to many reasons such as heavy metal ions and anions. In this regard, many researchers have studied organic materials to monitor above reasons to protect environmental pollution. One of the organic materials for this function is chemosensor. This chemosensor has been studied and reported about monitoring toxic heavy metal ions and anions. In this study, the dye sensor was designed and synthesized through reaction of Rhodamine 6G and 1,3-Indanedion. this dye sensor selective detected $Hg^{2+}$ metal ions while showing red color absorption and yellowish-green strong fluorescence emission compared to other heavy metal ions such as $Cu^{2+}$, $Hg^{2+}$, $Ag^{2+}$, $Zn^{2+}$, $Fe^{2+}$ and $Fe^{3+}$. In this regard, we anticipated that this dye senosr can provide an significant material for monitoring mercury which cause environmental pollution. Thus, We investigated detailed properties of this dye sesnor with using UV-Vis absorption and fluorescent spectrophotometer, Job's plot method for metal binding complex, computational simulated calculation named Material Studio 4.3 suite to approach for electron distribution and HOMO/LUMO.

• Journal of Power System Engineering
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• v.13 no.6
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• pp.76-81
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• 2009

Thermal desorption systems are designed to remove organic compounds from solid matrices such as soils, sludges and filter cakes without thermally destroying them. It is a separation technology, not a destruction technology. Since it is a thermal process, there is a common belief that temperature is the only significant parameter to be monitored. While it is true that better removal efficiencies are usually achieved at higher temperatures, other factors must be considered. Since the process is governed by mass transfer, heating time and the amount of mixing are also key parameters in optimizing removal efficiency. Thermal desorption have been successfully used for just about every organic contaminant found to date. It has also been used to remove mercury. In the present study, the numerical simulation has been performed to investigate the characteristics of heat transfer of LTTD(low temperature thermal desorption). The commercial software, AMESIM was applied for analyzing the heat transfer process in the LTTD.

• Korean Journal of Environmental Biology
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• v.28 no.4
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• pp.212-217
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• 2010

Soil pollution by heavy metals has become a significant environmental concern due to a variety of human activities. Specially toxicity caused by excessive mercury exposure is now being recognized as a widespread environmental problem and is continuing to attract a great deal of public concerns. The earthworms are very important animals that aerate the soil with their burrowing action and enrich the soil by decomposing organic matters. Especially the earthworm Eisenia fetida is routinely used in ecotoxicological studies. The levels of DNA damage in earthworms treated with HgCl2 and ionizing radiation were investigated in this study. Genotoxic effects were evaluated in the earthworm's coelomocytes using the comet assay (Single Cell Gel Electrophoresis; SCGE). The results showed that the mercury chloride and radiation were responsible for the genotoxic effects on earthworms. The level of DNA damage significantly increased after the treatment of mercury chloride combined with ionizing radiation. The combined treatment of $HgCl_2$ and ionizing radiation had a greater genotoxicity. This study is amenable to further study such as enzyme activation assay.

• Journal of Preventive Medicine and Public Health
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• v.39 no.3
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• pp.199-204
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• 2006

Objectives: Mercury is a hazardous organ-specific environmental contaminant. It exists in a wide variety of physical and chemical states, each of which has unique characteristics for the target organ specificity. Exposure to mercury vapor and to organic mercury compounds specifically affects the CNS, while the kidney is the target organ for inorganic Hg compounds. Methods: In this study, mercury chloride $(HgCl_2)$ was studied in a renal derived cell system, i.e., the tubular epithelial Madin-Darby canine kidney (MDCK) cell line, which has specific sensitivity to the toxic effect of mercury. MDCK cells were cultured for 6-24 hr in vitro in various concentrations (0.1-100 M) of $HgCl_2$, and the markers of apoptosis or cell death were assayed, including DNA fragmentation, caspase-3 activity andwestern blotting of cytochrome c. The influence of the metal on cell proliferation and viability were evaluated by the conventional MTT test. Results: The cell viability was decreased in a time and concentration dependent fashion: decreases were noted at 6, 12 and 24 hr after $HgCl_2$, exposure. The increases of DNA fragmentation were also observed in the concentrations from 0.1 to 10 M of $HgCl_2$ at 6 hr after exposure. However, we could not observe DNA fragmentation in the concentrations more than 25 M because the cells rapidly proceeded to necrotic cell death. The activation of caspase-3 was also observed at 6 hr exposure in the $HgCl_2$ concentrations from 0.1 to 10 M. The release of cytochrome c from the mitochondria into the cytosol, which is an initiator of the activation of the caspase cascade, was also observed in the $HgCl_2-treated$ MDCK cells. Conclusions: These results suggest that the activation of caspase-3 was involved in $HgCl_2-induced$ apoptosis. The release of cytochrome c from the mitochondria into the cytosol was also observed in the $HgCl_2-treated$ MDCK cells. These findings indicate that in MDCK cells, $HgCl_2$ is a potent inducer of apoptosis via cytochrome c release from the mitochondria.

• Korean journal of applied entomology
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• v.18 no.2 s.39
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• pp.63-71
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• 1979

Tests were made to find new non-mercurious seed disinfectants that were best for rice seeds. For these experiments four seed samples carr)?ing natural infection of Pyricularia oryzae, Helminthosporium oryzae, and Fusarium moniliforme were used and the following fungicides were used; Zinc Omadine, Sodium Omadine, Panoctine, Tecto-F, Benlate-T, Homai, Sisthane, $P_{242}$, Busan 30, Tecto-Wp and Terracoat Zn. Blotter method and water agar plate method used in the laboratory and growing-on test used in greenhouse. Results have shown that Sisthane, $P_{242}$ and Sodium Omadine have equal or superior effect to organic mercury compound against P. oryzae, H. oryzae, and F. moniliforme. Benlate T and Homai are effective against blast and Bakanae disease, but are inferior to organic mercury compound against brown spot disease. Busan 30 and Panoctine are effective against blast and brown spot disease, but have moderately inferior effects against F. monilifome. It is considered that the recommendable testing methods of seed treatment were blotter method for P. oryzae and water agar plate method for H, oryzae and F. moniliforme according to the experimental results obtained. No phytotoxicity against seed germination and seedling growth were observed when treated with disinfectants before germination of seeds.

• Journal of Korean Society of Water and Wastewater
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• v.17 no.4
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• pp.542-549
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• 2003

In the present study, the feasibility of $UV/H_2O_2$ systems was investigated using low and medium-pressure lamps on biologically treated wastewater effluents for secondary effluent reclamation. Two types of UV lamps were used as the light sources (a 39-W low-pressure mercury lamp and a 350-W medium-pressure mercury lamp). The results from these UV systems showed that the removal of organic compounds could be achieved in the contact time of longer than 30min (i.e., low UV doses). Efficiencies of color removal and disinfection were far better than those of organic matters measured as TOC, DOC and $TCOD_{cr}$. In the low-pressure lamp UV system, it has been found that DOC and color removals were 60.9 and 86.2% with 50mg/L of $H_2O_2$ and contact times of 30 minute, respectively. Whereas, with the medium-pressure lamp UV system, TOC, DOC and color removal were 27.1, 5.6 and 95% with 14.3mg/L of $H_2O_2$ and 14 minute of contact times, respectively. Both systems could be applied for the reclamation of secondary effluent treated with biological treatment processes.

• Applied Chemistry for Engineering
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• v.10 no.1
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• pp.30-34
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• 1999

Photolysis behavoirs of pesticides(Chlorothalonil and Endosulfan) over UV irradiation UV irradiation with pH 3.0 and irradiation with 3.5% salt were studied. The analyses of pesticides were carried out using gas chromatograph with an electron-capture detector, total organic carbon, and Ion chromatograph, respectively. The reactions were conducted in a alumium annular reactor equipped with a low pressure mercury multilamp ($8W{\times}6$) and initial concentration was 10 ppm. Chlorothalonil was almost photodegraded by UV irradiation, UV irradiation with pH 3.0 and 3.5% salt within 30 min of reaction time. Endosulfan-${\alpha}$,${\beta}$(100%) were photodegraded to 38% of Endosulfan-${\alpha}$ and 25% of Endisulfan-${\beta}$ by UV irradiation. Endosulfan-${\alpha}$(83%) was photodegraded to 66% by UV irradiation, 70% by UV irradiation and pH 3.0 and 75% by UV irradiation and 3.5% salt. Endosulfan-${\beta}$(16%) was photodegraded to 80% by UV irradiation, 98% by UV irradiation and pH 3.0 and 90% by UV irradiation and 3.5% salt.

• Journal of the korean society of oceanography
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• v.33 no.4
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• pp.178-184
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• 1998

To elucidate contamination levels and distribution of methyl mercury (Me-Hg) in Korean coastal areas, 126 sediment samples were collected from Kyeonggi Bay, Namyang Bay, Chinhae Bay, and Lake Shihwa during 1995-1996, and the Me-Hg concentrations were determined by cold vapor atomic fluorescence spectrometry (CVAFS). Contamination levels of Me-Hg in sediments from Kyeonggi Bay, Namyang Bay, Chinhae Bay, and Lake Shihwa were 274 ${\pm}$ 990, 108 ${\pm}$ 24, 294 ${\pm}$ 342, and 1080 ${\pm}$ 760 pg/g, respectively. Concentrations of Me-Hg in sediments were significantly correlated with total organic carbon and sulfur contents, but were independent of mud contents and mean grain size. The highest concentration of Me-Hg (7100 pg/g) was observed at Incheon North Harbor (Site Kl9) in Kyeonggi Bay. This Me-Hg concentration was one or two orders of magnitude higher than those in other Kyeonggi Bay sediments were. The average concentration of Me-Hg in sediments from Lake Shihwa was higher than in those from other study areas. The three peaks of Me-Hg concentrations were observed on three sites (55, 56,and 510) in Lake Shihwa and gradually decreased in distance-dependent manner around these sites. High concentrations of Me-Hg at surface and 10-cm sediment depth in Chinhae Bay maybe due to higher rates of methylation process by active sulfate-reducing bacteria or higher concentrations of total mercury available to sulfate-reducing bacteria.

• Advances in environmental research
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• v.1 no.1
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• pp.15-35
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• 2012

Mercury (Hg) is a global environmental pollutant that has been the cause of many public concerns. One particular concern about Hg in aquatic systems is its trophic transfer and biomagnification in food chains. For example, the Hg concentration increases with the increase of food chain level. Fish at the top of food chain can accumulate high concentrations of Hg (especially the toxic form, methylmercury, MeHg), which is then transferred to humans through seafood consumption. Various biological and physiochemical conditions can significantly affect the bioaccumulation of Hg-including both its inorganic (Hg(II)) and organic (MeHg) forms-in fish. There have been numerous measurements of Hg concentrations in marine and freshwater fish worldwide. Many of these studies have attempted to identify the processes leading to variations of Hg concentrations in fish species from different habitats. The development of a biokinetic model over the past decade has helped improve our understanding of the mechanisms underlying the bioaccumulation processes of Hg in aquatic animals. In this review, I will discuss how the biokinetic modeling approach can be used to reveal the interesting biodynamics of Hg in fish, such as the trophic transfer and exposure route of Hg(II) and MeHg, as well as growth enrichment (the increases in Hg concentration with fish size) and biomass dilution (the decreases in Hg concentration with increasing phytoplankton biomass). I will also discuss the relevance of studying the subcellular fates of Hg to predict the Hg bioaccessibility and detoxification in fish. Future challenges will be to understand the inter- and intra-species differences in Hg accumulation and the management/mitigation of Hg pollution in both marine and freshwater fish based on our knowledge of Hg biodynamics.

• Advances in environmental research
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• v.2 no.2
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• pp.81-98
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• 2013

Mercury (Hg) dynamics in the boreal environment have been a subject of concern in recent decades, due to the exposure of local populations to the contaminant. Land use, because of its impact on mercury inputs, has been highlighted as a key player in the sources and eventual concentrations of the heavy metal. In order to evaluate the impact of watershed disturbances on Hg dynamics in frequently fished, large boreal lakes, we studied sediment cores retrieved at the focal point of eight large lakes of Qu$\acute{e}$bec (Canada), six with watersheds affected by land uses such as logging and/or mining, and two with pristine watersheds, considered as reference lakes. Using a Geographical Information System (GIS), we correlated the recent evolution of land uses (e.g., logging and mining activities) and morphological characteristics of the watershed (e.g., mean slope of the drainage area, vegetation cover) to total Hg concentrations (THg) in sedimentary records. In each core, THg gradually increased over recent years with maximum values between 70 and 370 ng/g, the lowest mercury concentrations corresponding to the pristine lake cores. The Hg Anthropogenic Sedimentary Enrichment Factor (ASEF) values range from 2 to 15. Surprisingly, we noticed that the presence of intense land uses in the watershed does not necessarily correspond to noticeable increases of THg in lake sediments, beyond the normal increment that can be attributed to Hg atmospheric deposition since the beginning of the industrial era. Rather, the terrestrial Hg inputs of boreal lakes appear to be influenced by watershed characteristics such as mean slopes and vegetation cover.